If I create a desktop file that updates correctly the way you describe, and I put it into a folder in the app menu along with some other apps, when executed it'll update but reappear outside the folder. I was looking around for somewhere to define it's location to keep it inside the folder (something in the .desktop files or… wasn't there .folder or .directory files in Fremantle?) but I can't see anything. Any ideas?
/home/nemo/.config/lipstick/applications.menu /home/nemo/.config/nemomobile/lipstick.conf